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evolution of primate

...a continuum of change from a hind limb-dominated gait to a forelimb-dominated one. The best single indicator of gait, one that has the added advantage of being strictly quantitative, is the
intermembral index. Briefly, the index is a ratio expressed as percentage of arm length to leg length; an index over 100 indicates relatively long arms. This provides a model by means of which the...